IN THB BRITISH ISLANDS. 115 



this genus. The interest in them has been greatly enhanced owing to 

 the discovery in the Shetland Isles of forms totally unlike those obtain- 

 able in England, Ireland and, so far, on the mainland of Scotland. Of 

 these Shetland examples, which are the true conflua, Mr. J. Jenner 

 Weir writes : " This insect varies much ; some resemble the ordinary 

 varieties of conflua, others are in coloration more like N. dahlii, and 

 others are very like N. brunnea ; all are darker than the normal N. 

 festiva. Some have a hoary appearance, and indeed present such 

 singular differences that I do not doubt, if the more remarkable aber- 

 rations were examined separately, they would, in the absence of links, 

 be regarded as distinct species " (' Entomologist,' vol. xiii., p. 289) ; 

 and, writing of ' the Lepidoptera of Unst,' the same gentleman remarks 

 again of true conftua : " A most beautiful series of this species was 

 captured, some of a very rich chestnut colour with well-defined 

 markings, as rich in colour as N. brunnea ; and others of the var. con- 

 flua with markings almost obsolete. Of these, three varieties are 

 figured,* Nos. 8, 9 and 10" (' Entomologist,' vol. xvii., p. 2). Of the 

 general variation of ordinary JVoctua f estiva, Newman writes : " This 

 moth is exceedingly variable. Through the kindness of friends I have 

 at times possessed hundreds of specimens, of which I can truly say 

 that no two were exactly alike " (' British Moths,' p. 349). The end- 

 less variation to which this species is subjected, the remarkable 

 connection between this and the small race, erroneously known as 

 conflua, which is captured on the moors of North England and in 

 Scotland, together with the occurrence of the true conflua (agreeing 

 exactly with Icelandic specimens) in the Shetland Isles with festiva, 

 make this one of the most interesting of our NOCTILSJ. 



The small form of festiva, generally known as conflua in Britain 

 and on the Continent, is not the conflua of Treitschke, which represents 

 the Shetland and Iceland form lately introduced into our lists as var. 

 thulei. I have not the remotest doubt that this true Iceland and Shetland 

 conflua is a good and distinct sub-species, having nothing in common 

 with the small specimens of festiva which are picked out from hundreds of 

 the larger forms by our Scotch collectors, and distributed broadcast into 

 our English collections as conflua. This error was due primarily to New- 

 man, who treated this small race of festiva as a distinct species under the 

 name of conflua in his ' British Moths,' p. 349, erroneously supposing that 

 these small festiva were Treitschke's conflua. Of Newman's so-called 

 conflua, Mr. Reid of Pitcaple writes : " There is no difference between 

 the specimens sent out from Aberdeenshire as festiva and conflua. 

 Collectors pick out all the small specimens and call them conflua (because 

 it is so in Newman's ' British Moths '), and all the large ones and call 

 them festiva. They (both large and small) occur together here in all 

 localities, almost from the sea-level to several hundred feet above the 

 sea " (in litt.). I have some two hundred specimens in my series from 

 different localities in Scotland and England, and it is impossible to get 

 from the mainland of Scotland, so far as we at present know, a single 

 form that cannot be obtained occasionally in our Kent woods. Some 

 of my smallest examples are from Kent, and some of my largest from 

 Perth and Aberdeen. Of course, local environment causes some little 

 difference in the appearance of such a common species, and a tendency 

 to glaucous is more frequent in the Aberdeen and Darlington districts 



* The figures are very bad, and utterly useless for reference. J. W. T. 



